Solaris and Linux: No Code Swapping

Sun refuses to reconsider licensing Solaris under GPL 2.0, and Linux Torvalds says Linux will not migrate to GPL 3.0, closing the door on any chance of co-mingling of code between the two operating systems.

While Sun Microsystems is open to licensing Solaris under Version 3.0 of the GNU General Public License, it will not reconsider its decision not to license the operating system under GPL 2.0, the current version of the license.

Sun created the CDDL (Community Development and Distribution License) for Solaris after rejecting GPL 2.0 as too restrictive for its purposes.

Sun will not consider licensing Solaris under the current GPL for the same reasons it gave when it created the CDDL, which is based in large part on the MPL (Mozilla Public License), Tom Goguen, Suns vice president of software marketing, told eWEEK in an interview.

/zimages/4/28571.gifThe first discussion draft of GPL 3 addresses the issues of patents and patent-related retaliation, as well as its compatibility with other licenses. Click here to read more.

"We wanted to enable as broad a development community as possible around Solaris, and one part of that is being able to prescribe what you can and cannot do with the code, what other code you can combine with it, and exactly how to do it," he said.

This is one of the strengths of the MPL, on which Sun modeled the CDDL, compared with the "all-or-nothing scenario under the current GPL, which also says nothing about patents, and Im not sure how far the next version will go there," he said.

/zimages/4/28571.gifClick here to read more about how Sun has been criticized for the limitations of its patent release.

While Sun is not taking a position on software patents, it will not disagree that most people feel they are very problematic, "but they are the one instrument that we have to work with today, and so we needed a license that addressed that," he said.

Suns refusal to reconsider licensing Solaris under GPL 2.0 also appears to effectively remove any chance that code from that software can be co-mingled with that from the open-source Linux operating system, which is currently licensed under GPL 2.0. Thats because Linus Torvalds, the Linux kernel project leader, has said that he has no plans to relicense the Linux kernel under GPL 3.0 when it is released early next year.

"I dont think the GPL 3.0 conversion is going to happen for the kernel, since I personally dont want to convert any of my code," Torvalds said.

/zimages/4/28571.gifRead more here about Torvalds decision not migrate Linux to GPL 3.0.

Thus, if the Linux kernel code does not get licensed under GPL 3.0, even if Solaris does, the current restrictions on the co-mingling of code from the two operating systems will essentially remain in force.

In fact, when Sun submitted the CDDL to the Open Source Initiative for approval, Claire Giordano, a member of Suns CDDL team, said as much in a letter accompanying the submission.

"Like the Mozilla Public License, the CDDL is not expected to be compatible with the GPL [2.0], since it contains requirements that are not in the GPL. Thus, it is likely that files released under the CDDL will not be able to be combined with files released under the GPL to create a larger program," she said.

Next Page: Benefits, challenges of going to GPL 3.0.